We were having a discussion as to whether or not you must "set the lines" after replacing a line set on a parachute. By setting the lines I mean doing a sub-terminal opening before taking the brand new line set to terminal.

We were having a discussion as to whether or not you must "set the lines" after replacing a line set on a parachute. By setting the lines I mean doing a sub-terminal opening before taking the brand new line set to terminal.

Thoughts or ideas??????

Thanks

I don't think there is anything in the manuals from the mfgs about that, so I would say you are already getting their advice in their manual.

We were having a discussion as to whether or not you must "set the lines" after replacing a line set on a parachute. By setting the lines I mean doing a sub-terminal opening before taking the brand new line set to terminal.

You missed my point. Any new canopy effectively is a reline, and the lines aren't "set." Neither a new main nor a new reserve have the lines "set" but nobody worries about setting those lines. My questions were intended to argue against the need to set lines on a relined main.

We were having a discussion as to whether or not you must "set the lines" after replacing a line set on a parachute. By setting the lines I mean doing a sub-terminal opening before taking the brand new line set to terminal.

Thoughts or ideas??????

Thanks

Complete crap. Just another case of over-think on someone's part. When in doubt, call John LeBlanc.

I wonder if "stretching the lines" made sense in the days of ParaCommanders due to the high stretch of the 550 cord. To what degree lines actually took a relatively permanent "set", I don't know. (It won't quite be the same as just the elastic vs. plastic region for deformation of material, as we are talking about woven material.)

When the industry got into Spectra, there some stretching is done at the factory. After all, one can't cut Spectra line to a consistent length unless one applies some force to take the initial stretch out of it.

One reason to do a hop and pop on a new canopy is as a quality control check to see that it is flying OK. Perhaps safer at lower speed (and higher altitude) than at terminal (and lower down.) (And of course a hop and pop can be a quality control check for the jumper's piloting skills too...)

I wonder if "stretching the lines" made sense in the days of ParaCommanders

Having read nearly all of yours posts since I joined this dizzy.com group, you should have been around in the 60's. You would have thrived in the 'discussions' back then.

I.e., two subjects for 'discussion' were:

- Did you have to take a new canopy on a couple of hop 'n' pops to 'set the lines' or not. Some argued you had to and some just took their new ParaCommanders out to terminal and moved on. How many people back then took their new Security 26 ft conical reserve canopies on hop 'n' pops to 'set the lines?' Nope, no one; and if you had to use it at terminal it did seem to work OK.

- Piggyback vs conventional gear; conventional gear was main on the back & reserve in a gut pack.

I think the actual issue is more about low altitude and short delay when trying a new parachute system or jumping a rig for the first time. I would not worry particularly about lines to be set but about anything which can go wrong because of the rig or because of the jumper. When jumping a new system, it is a good idea of trying it for a short delay just because that involves less opening forces, just in case something let go. Also trying a new system at low altitude makes that if something goes wrong and you need to cut away, you will have less chance to lose your main and free bag/pilot chute. I know a guy who was jumping a used rig for the first time and jumping at high altitude. For whatever reason, it became unstable and decide to cut away at 10 000 feet or so. Well he lost his main.

When jumping a new system, it is a good idea of trying it for a short delay just because that involves less opening forces, just in case something let go.

'Back in the day' when the Visions/Coors 8-way team got their new US Team rigs, Craig Fronk just strapped his new rig on & went up on a jump; only to find the main canopy on backwards. It had come that way from whomever had assembled & packed the US Team rigs.